How extraordinary it is to have a major Hollywood feature film with an idealistic American Communist, sympathetically depicted, as its hero. Hollywood is where the merest supposition of sympathy for anything like communism once wiped out careers like the plague.

But Warren Beatty's "Reds" is an extraordinary picture. Three hours and 19 minutes long, it is occasionally rambling and repetitious, but nearly always intelligent and engrossing. This is a new type of biographical film of which another example is "Priest of Love," about Frieda and D.H. Lawrence. (Not only is the period the same, but the two men had a common friend, as it were, in Mabel Dodge.) Both movies have broken through the silly but prevalent movie convention that an individual can engage in passions of the mind or of the body, but not both. These films show, with bittersweet humor, both the glories and the foibles, in public and in personal life, of eccentric intellectuals.

"Reds" is about John Reed, journalist, political organizer and author of "Ten Days That Shook the World," and his wife, journalist Louise Bryant, who was also involved with playwright Eugene O'Neill. Filmed reminiscences of them by a galaxy of contemporary figures are interspersed with the action. These include Henry Miller, Dora Russell, Rebecca West, Will Durant, Isaac Don Levine, Adela Rogers St. Johns, George Jessel, Hamilton Fish -- several of them dead since the film was made -- and it is a shortcoming that the film does not identify them by name as they appear, as if it were some sort of high level test to be able to recognize these people in their extreme old age.

The theme of conflicting individuality and collective identity is presented in dozens of different ways, from Reed's objections to having his work rewritten, first by an American editor and later by the Communist Party, to his wife's difficulties in establishing a separate reputation for herself in his field among his friends. It all naturally leads to a good deal of shouting, whether between lovers or among delegates at meetings, and in ways both funny and sad, one sees how the desperate need of the individual voice to be heard leads to its pronouncing a great deal of inflated nonsense.

Beatty, who directed the film and wrote it with Trevor Griffiths, has to go against his healthy, boyish looks to play the role of Reed, and his good efforts are sometimes thwarted by the fact that he looks so much at home in the world the way it is. Diane Keaton, as Louise Byrant, has no such difficulty, and epitomizes the outrageous sexiness of the loud and slovenly freedom fighter. Their quarrels, in which lofty statements about the principle of free love are juxtaposed with narrow-eyed demands of "Who?" and "How many?", are magnificent.

Jack Nicholson, a stolid actor whose only resemblance to O'Neill is in the mustache, is nevertheless wonderfully lean and sardonic in his characterization. Two of the film's great moments are when he follows one of Louise's parlor manifestoes with the question "Are you making this up as you go along?" and another with "Something in me tightens whenever an American intellectual's eyes shine." Other treasures are the far- too-few scenes in which Maureen Stapleton plays Emma Goldman as if anyone who stands in her way is going to be mowed down by the sheer force of her righteousness, and the amazingly adept appearances of two non-actor celebrities, novelist Jerzy Kosinski as a Bolshevik and writer George Plimpton as an upper-class ass. But there is hardly a fleeting character in this long film not memorably played; one is left, as if it had been a superb photographic exhibition from the period, with dozens of haunting faces.

There are only a few outright mistakes in the film, besides the failure to identify the interview subjects: the tiresomely cute motif of having the dog scratch at the bedroom door each time Reed and Byrant are making love; Emma Goldman's employing the modern erroneous use of the word "hopefully"; the repeated joke of having Reed hit his head on a Czarist-era chandelier hung inexplicably low. Editing was needed, not because the film is long, but because it goes around the same track, or wanders off the track.

But it is an extraordinary film.

REDS -- At the Beltway Plaza, Fairfax Circle, K-B Cinema, K-B Cinema 7, K-B Congressional 5, K-B MacArthur, K-B Silver, NTI Tyson's Cinema, Springfield Mall.